1. Field of the Invention
The invention relates generally to medical laser treatments performed beneath the skin and more specifically to correction of skin disfigurement, to eradication of vascular abnormalities, and to various operations performed on internal body structures.
2. Invention Disclosure Statement
Underskin laser treatment is an effective way to eliminate many abnormalities. A below the skin application provides a more proximal access to the area of treatment enabling the use of a less powerful and less harmful laser. Straight form surface treatments require laser energy to be focused on the skin surface, commonly leading to undesired side effects such as external discoloration or scarring. The present invention describes an underskin laser treatment system that can be utilized for correcting skin irregularities, eradicating vascular abnormalities, and operating in various parts of the body. Radiation administered below the surface of the skin provides a more proximal application with reduced risks of accidentally exposing surrounding tissue to the laser radiation.
Dermatological laser treatments have been reported to cure skin wrinkles. Laser energy is used to selectively trigger the body's normal healing process. Effectively, the lasing induces fibroblast activity resulting in collagen proliferation. The wrinkle is filled in and thereby reduced. The method involves flashing a laser onto the skin surface above the wrinkle to induce underskin effects. The desired area of treatment however lies beneath the skin surface. The laser energy must penetrate the epidermal layer to reach the derma. This distance of the beam from the treatment site and the loss of energy due to reflection of the beam at the skin surface necessitate using a higher power laser. As a result, potential, undesired surface damage occurs. Such damage may include prolonged erythema, scaring, dyspigmentation, and infection. To prevent these side effects, one laser method employs a cryogen spray that is projected onto the epidermis during treatment to counteract the laser heat energy. The cooling part of the process allows users to selectively effect the derma while protecting the overlying layers. The success and safety of the procedure then depends greatly on the consistent application of the coolant. Further, devices needed to dispense the coolant, for example a coolant reservoir on the laser delivery device, makes the invention more complex and potentially more expensive and cumbersome. [See, e.g., Kristen M. Kelly et. al., "Cryogen Spray Cooling in Combination With Nonablative Laser Treatment of Facial Rhytides," Arch. Dermatol., 135 (1999) 691-694., J. Stuart Nelson, M D, PhD et. al., "Dynamic Epidermal Cooling During Pulsed Laser Treatment of Port-Wine Stain," Arch. Dermatol., 131 (1995) 695-700., Bahman Anvari et. al., "A Theoretical Study of the Thermal Response of Skin to Cryogen Spray Cooling and Pulsed Laser Irradiation: Implications For Treatment of Port Wine Stain Birthmarks," Phys. Med. Biol., 40 (1995) 1451-1465.]
The present invention describes an improved method of wrinkle removal. By allowing laser energy to be delivered subcutaneously, the present invention substantially prevents against surface epidermal injury. Further, the closer proximity of the application of the radiation to the underskin site allows a lower power application reducing the amount of deleterious side effects in general.
Laser treatment below the surface of the skin has also been described in U.S. Pat. No. 5,531,739 to Trelles. There a method is described whereby an optical probe is inserted into the skin adjacent to a vascular abnormality. Introducing laser pulses will serve to collapse and close off the vein. This method requires multiple insertions of the device along the desired vein to treat the abnormality. The procedure has limitations. First, the described method is specific for treatment of veins, primarily in the leg, and is therefore limited to that specific treatment. Second, the procedure requires a low power beam to illuminate and direct the probe to the treatment site under the skin. Treatment is then limited to underskin sites at a depth that the illumination beam can penetrate. Third, the method describes delivery of the laser power to the vicinity of, and outside the vein requiring treatment. Such laser treatment closes off the vein by collapsing its wall, an indirect solution.
In addition, U.S. Pat. No. 5,578,029 to Trelles et. al. describes a device that can be used to perform the underskin laser treatment of veins. The composition of the device described further limits the practicality of the invention. First, the device employs probes specially manufactured for the procedure, increasing the specificity of the equipment needed. Therefore, it may be difficult for users to have on hand all the various sized probes needed for different applications; and it may be costly for them to obtain additional attachments. Second, the special probes used in the treatment are too expensive to be disposed of; therefore they must be sterilized and sharpened after applications. This is both time consuming and cumbersome for the user. Time and effort are required to ensure that each probe is properly sterilized; and suitable sharpening depends on the care and skill of the user.
The method also requires multiple insertions of the device into the patient's skin. Each insertion must be made so that the probe is placed in close proximity to the vein being treated. The treated section of the vein is closed off, the device is removed, reinserted into another section of the vein, and the lazing procedure is repeated. This requirement makes the device more difficult to use. Further, by introducing multiple punctures of the skin the risk of infection is increased, as is the chance for disfiguration of the skin surface.
Therefore, a device that incorporates a standard, less costly and more readily available needle or probe would be beneficial. Further, there exist a vast number of subcutaneous aberrations to which underskin laser treatment may be applied. The aforementioned limitations prevent the device and method outlined in Trelles from being used.
The present invention is designed to employ standard, disposable needles of varying specifications by which to introduce any size laser carrying optical fiber required to a subcutaneous treatment site. The device and method may be used on all body structures that can be affected by laser treatment. Users may therefore apply treatment with the present invention on superficial as well as internal organs and tissues.
An aim of the present invention is to provide a device and method to safely and effectively treat underskin abnormalities through direct contact, without incurring the problems and deleterious side effects associated with the prior art.